Question 1 :
During extraction of metals, electrolytic refining is used to obtain pure metals. Suggest a suitable electrolyte for refining of silver metal by this process.
Question 2 :
A non-metal A which is the largest constituent of air, when heated with $H_2$ in 1 : 3 ratio in the presence of catalyst (Fe) gives a gas B. On heating with $O_2$ it gives an oxide C. If this oxide is passed into water in the presence of air it gives an acid D which acts as a strong oxidising agent. The products are identified to be A-$N_2$, B-$NH_3$, C-NO, D-$HNO_3$. Is the identification correct?
Question 3 :
An element A burns with golden flame in air. It reacts with another element B, atomic number 17 to give a product C. An aqueous solution of product C on electrolysis gives a compound D and liberates hydrogen. Identify C
Question 4 :
If copper is kept open in air, it slowly loses its shining brown surface and gains a green coating. It is due to the formation of
Question 6 :
A non-metal A is an important constituent of our food and forms two oxides B and C. Oxide B is toxic whereas C causes global warming. Identify A.
Question 7 :
A metal A, which is used in thermite process, when heated with oxygen gives an oxide B, which is amphoteric in nature. Identify A
Question 8 :
Generally, when metals are treated with mineral acids, hydrogen gas is liberated but when metals (except Mn and Mg), treated with $HNO_3$, hydrogen is not liberated because
Question 9 :
Although metals form basic oxides, which of the following metals form an amphoteric oxide?
Question 10 :
Metals are refined by using different methods . Which of the following metals are refined by electrolytic refining?
(i) Au
(ii) Cu
(iii) Na
(iv) K
Question 12 :
An element forms an oxide $A_2O_3$ which is acidic in nature. Is A a metal or a non-metal?
Question 13 :
Compound X and aluminium are used to join railway tracks. The reaction taking place is called 'Thermite reaction'. Is this statement TRUE or FALSE?
Question 14 :
Generally, non-metals are not lustrous. Which of the following non-metal is lustrous?
Question 15 :
A non-metal A is an important constituent of our food and forms two oxides B and C. Oxide B is toxic whereas C causes global warming. Identify B.
Question 16 :
State True or False : Carbon can reduce the oxides of Na or Mg
Question 17 :
Stainless steel is very useful material for our life. In stainless steel, iron is mixed with
Question 18 :
When a metal X is treated with cold water, it gives a basic salt Y with a molecular formula XOH (Molecular mass = 40) and liberates a gas Z which easily catches fire. Identify Z
Question 20 :
Which of the following properties is not generally exhibited by ionic compounds?
Question 21 :
During extraction of metals, electrolytic refining is used to obtain pure metals. In this electrolytic cell, while refining silver metal, where do we get pure silver after passing electric current?
Question 22 :
State True or False : Metals like Na, K, Ca and Mg are found in their free state in nature.
Question 23 :
Which of the following metals are obtained by electrolysis of their chlorides in molten state?
(i) Na
(ii) Ca
(iii) Fe
(iv) Cu
Question 24 :
2 mL each of concentrated HCl, $HNO_3$ ans a mixture of concentrated HCl and concentrated $HNO_3$ in the ratio 3 : 1 were taken in a test tubes labelled as A, B and C. A small piece of metal was put in each test tube. No change occured in test tubes A and B but the metal got dissolved in test tube C respectively. The metal could be
Question 25 :
A non-metal X exists in two different forms Y and Z. Y is the hardest natural substance, whereas Z is a good conductor of electricity. What is Y?
Question 26 :
An alkali metal A gives a compound B (molecular mass = 40) on reacting with water. The compound B gives a soluable compound C on treatment with aluminium oxide. Identify B
Question 27 :
An alkali metal A gives a compound B (molecular mass = 40) on reacting with water. The compound B gives a soluable compound C on treatment with aluminium oxide. Identify C
Question 28 :
A non-metal A which is the largest constituent of air, when heated with $H_2$ in 1 : 3 ratio in the presence of catalyst (Fe) gives a gas B. On heating with $O_2$ it gives an oxide C. If this oxide is passed into water in the presence of air it gives an acid D which acts as a strong oxidising agent. To which group of periodic table does this non-metal belong?
Question 29 :
A non-metal X exists in two different forms Y and Z. Y is the hardest natural substance, whereas Z is a good conductor of electricity. What is X?
Question 30 :
During extraction of metals, electrolytic refining is used to obtain pure metals. Which material will be used as anode and cathode for refining of silver metal by this process?
Question 31 :
Of the three metals X,Y and Z. X reacts with cold water, Y reacts with hot water and Z with steam only. Identify Z
Question 32 :
A solution of $CuSO_4$ was kept in an iron pot. After few days the iron pot was found to have number of holes in it. So, we can conclude that
Question 35 :
State True or False : NaCl is not a conductor of electricity in solid state whereas it does conduct electricity in aqueous solution as well as in molten state
Question 36 :
The electronic configurations of three elements X, Y and Z are X-- 2,8; Y-- 2,8,7 and Z-- 2,8,2. Which of the following is correct?
Question 37 :
An element A reacts with water to form a compound B which is used in white washing. The compound B on heating forms an oxide C which on treatment with water gives back B. Identify A
Question 38 :
An element A reacts with water to form a compound B which is used in white washing. The compound B on heating forms an oxide C which on treatment with water gives back B. Identify B
Question 39 :
Aluminium is used for making cooking utensils. Which of the following properties of aluminium are responsible for the same?
(i) Good thermal conductivity
(ii) Good electrical conductivity
(iii) Ductility
(iv) High melting point
Question 40 :
Give the formula of the stable binary compounds that would be formed by the combination of following pairs of element.
Li and $O_2$
